The present invention relates to a trailer, container and other transport vehicle and, more particularly, to an upper coupler or “king pin” of such a trailer, container or transport vehicle. The king pin couples the trailer to the truck that tows the trailer. The vertically-oriented king pin extends through a hole in a horizontally-oriented upper coupler plate which supports electrical lines and air lines that extend between the truck and the trailer. The steel upper coupler plate includes other through holes through which the electrical lines and pneumatic lines may be accessed.
A problem is that objects may fall out of these holes. In particular, the wiring harnesses and pneumatic lines may fall out of the holes. The excess wiring may be bundled up and pushed into a rectangular shaped chamber that is inside the hole and at least partially defined by the coupler plate. As may be readily appreciated, harnesses may occasionally fall through the holes and become snagged on the truck, causing warranty and functionality issues.
Another problem is that foreign objects and materials, such as water, snow, salt, bees, birds, etc., may enter the chamber through these holes. It has been found that excess moisture and particularly road salts cause corrosion inside of the couplers. It has also been found that bees, birds, and other pesky animals like to make their homes inside of these holes. This causes a hassle when the trailer has to be worked on, especially in the front area.